1. Field of the Invention
This invention is concerned with the oxidative dehydrogenation of ethyltoluenes to the corresponding methylstyrenes.
2. Description of the Prior Art
Various processes have been proposed for the oxidative dehydrogenation of organic compounds to the corresponding unsaturated compounds. U.S. Pat. No. 3,403,192, which is incorporated herein by reference, discloses a vapor phase oxidative dehydrogenation process using oxygen and hydrogen sulfide in contact with a metal, metal oxide, or a metal hydroxide catalyst, usually with a promoter. Good conversions of ethylbenzene to styrene were achieved in the patented process, for example, but the dehydrogenation of ethyltoluene to methylstyrene often poses additional problems because of the vulnerability of the methyl group in the ethyltoluene to decomposition. Indeed, many prior art catalysts and processes which are entirely suitable for use in the dehydrogenation of ethylbenzene are found to result in poor conversion and selectivity when applied to the dehydrogenation of ethyltoluene.